at90ls4433 ATMEL Corporation, at90ls4433 Datasheet - Page 78

• Manufacturer Part Number: at90ls4433
• Description: At90s4433 8-bit Avr Microcontroller With 4k Bytes Of In-system Programmable Flash
• Manufacturer: ATMEL Corporation

Port C Data Register – PORTC
Port C Data Direction Register
– DDRC
Port C Input Pins Address –
PINC
Port C as General Digital I/O
78
AT90S/LS4433
The Port C Input Pins address (PINC) is not a register; this address enables access to
the physical value on each Port C pin. When reading PORTC, the Port C Data Latch is
read, and when reading PINC, the logical values present on the pins are read.
All six pins in Port C have equal functionality when used as digital I/O pins.
PCn, general I/O pin: The DDCn bit in the DDRC Register selects the direction of this
pin. If DDCn is set (one), PCn is configured as an output pin. If DDCn is cleared (zero),
PCn is configured as an input pin. If PORTCn is set (one) when the pin is configured as
an input pin, the MOS pull-up resistor is activated. To switch the pull-up resistor off,
PORTCn has to be cleared (zero) or the pin has to be configured as an output pin.The
port pins are tri-stated when a reset condition becomes active, even if the clock is not
running.
Table 25. DDCn Effects on Port C Pins
Note:
Bit
$15 ($35)
Read/Write
Initial Value
Bit
$14 ($34)
Read/Write
Initial Value
Bit
$13 ($33)
Read/Write
Initial Value
DDCn
0
0
1
1
1. n: 5..0, pin number
PORTCn
R
R
R
0
7
–
0
7
–
0
7
–
0
1
0
1
R
R
R
0
6
–
0
6
–
0
6
–
Output
Output
Input
Input
I/O
PORTC5
PINC5
DDC5
R/W
R/W
N/A
R
5
0
5
0
5
Pull-up
Yes
No
No
No
PORTC4
PINC4
DDC4
R/W
R/W
N/A
(1)
R
4
0
4
0
4
Comment
Tri-state (high-Z)
PCn will source current if ext. pulled low.
Push-pull Zero Output
Push-pull One Output
PORTC3
PINC3
DDC3
R/W
R/W
N/A
R
3
0
3
0
3
PORTC2
PINC2
DDC2
R/W
R/W
N/A
R
2
0
2
0
2
PORTC1
PINC1
DDC1
R/W
R/W
N/A
R
1
0
1
0
1
PORTC0
PINC0
DDC0
R/W
R/W
N/A
1042H–AVR–04/03
0
0
0
0
0
R
PORTC
DDRC
PINC